<AttributeFilter> element is used to configure plugins that filter incoming attributes to prevent applications protected by an SP from seeing data that violates whatever policies the filter implements.
While there are no specifically "mandated" points at which filters run, the SP generally invokes filtering immediately prior to the caching of a set of attributes into a user's session. Actually performing the filtering process is typically up to an Assertion Consumer Service handler (in the case of attributes delivered during SSO) or an attribute resolver.
type="XML", implements an XML-based policy language that is equivalent to the language supported by the IdP for control over attribute release. Most (though not all) of the features of the IdP's Java implementation are supported with the following exceptions:
For the time being, refer to the IdPAddAttributeFilter topic.
The XML attribute filter's XML "portion" is a reloadable resource, which means that the XML content can be supplied inline, in a local file, or a remote file, and can be monitored for changes and reloaded on the fly. The root of the XML instance MUST be an <afp:AttributeFilterPolicyGroup> element.
Inherits attributes supported by reloadable resources.
type="Chaining", wraps a set of filtering plugins so that they execute in sequence. The input to each plugin depends on the output of the previous one.
With V2.4 and above, this is implied by any configuration with multiple
<AttributeFilter> elements, so is no longer explicitly needed.
AttributeFilter(one or more)